Measurement devices for measuring the distance between the sensor and the surface of a medium (in other words the “fill level” or level) and the flow speed and flow direction of the medium are known which consist of two different measurement systems for detecting the distance (measurement system 1) and the flow speed (measurement system 2).
The distance is detected by way of a pulsed radar system. By contrast, the flow speed is determined by a different system which uses Doppler evaluation of a constant transmission signal, also known as a CW signal, CW standing for continuous wave.